Ford Focus HVAC Control Broken

We have had a 2007 Ford Focus hatchback for quite a while now and every winter we would notice that the HVAC control knobs got harder and harder to turn. Eventually, we ended up turning it too hard one day and it didn’t adjust the airflow anymore.

We took it to a mechanic and to the local Ford dealership. They told us it would cost $1000 to tear apart the whole dash and fix the problem. I recently discovered that the knob mechanism was entirely accessible with only a bit of tear down.

There are cables that attach the knob down, under the steering wheel, to the shutter doors that open and change the airflow. Since the knob could move freely, I figured that the knob or cables were broken. After plenty of YouTube research and playing around, I discovered that not only had the cables slipped out of their pulling locations due to stretching, but the knob was also slipping on the gear. After lots of gluing and tinkering, I finally got the whole thing working. That is the only problem for some people, but I had further problems with the shutter doors sticking. I fixed the symptoms, but the initial problem still needed fixing. I’ll cover that in the next post.

Changing Lawnmower Bearings

I was mowing the other day and a scraping sound started being emitted from the mower deck. Being the tractor loving person that I am, I was soon on my hands and knees investigating these unexpected sounds. I quickly discovered that the blades were scraping the deck because they were wobbling. I figured that a bearing came out so I took the deck off. It took quite a bit of hammering to get the bearing housing off the deck.

That was just the beginning of the hammering. Somehow, I haven’t really hammered my mechanical projects that much which shows my limited experience. The housing required a lot of hammering to get apart!

The new bearings were hard to get back on but they made a big difference. Not only did the blades not hit the deck anymore but the grinding, hurricane sound was gone! Although this job takes a bit of work it really makes a big difference.

Fixing A String Trimmer

I got my first string trimmer a couple of years ago, but immediately ran into trouble the next summer because I didn’t know how to winterize my gas powered tools. In fact, I just left it outside under the deck, and after a cold winter, as anyone who knows anything about engines would know, it didn’t start. I got some help from a friend, and he thought it was a problem with bad gas, which is a common problem with leaving gas in extreme weather.

The first thing we tested was the spark plug. I actually broke it when pulling it out, so there was no question about whether or not it needed replacing. I bought a new one, and still it wasn’t working. At this point we should have tested again for spark, but we didn’t think that gas was getting in there. This is where I learned a little trick to get small engines started. We took an eyedropper full of gas and squirted it into the cylinder beneath the spark-plug, carefully re-threaded the spark-plug (so as to not break it), and gave it a few pulls. Now, although this didn’t work in this case due to other problems that I still need to explain, this trick has come in handy in other circumstances.

So, what was the problem? Well, I set about testing for a spark by touching the metal of the spark-plug to metal on the engine (while the spark plug was still attached to the cable coming from the ignition coil), and pulling the starting cable. In my case there was no spark, but you should see a blue spark jumping across the two contacts of the spark-plug. Of course, yours could be dirty, but mine was brand new. Here is a YouTube video explaining how you can do this. Do take caution, because the spark produced could lead to death, so don’t be touching the metal, and keep it away from gas while testing it!

stringtrimmer

I also set about testing the kill switch just in case it was constantly on. I tested it by simply unplugging it and then trying to start the string trimmer again. This also didn’t produce the intended results. In my mind, there could only be one more reason there was no spark and that was the ignition coil. I looked it up online how to test it with a multi meter, and sure enough it was broken. Ignition coils can be expensive, but I found a replacement for a reasonable price. After some clean up, and installing the new ignition coil, it now runs great.

I guess I learned my lesson about winterizing my gas tools, but that shouldn’t break the ignition coil right? Well, there are two things that greatly contribute to ignition coil breakdown. One is excessive shaking, but my string trimmer runs really nice. The other thing is too much heat. Now, that summer, before it broke, I ran it like a horse, always at full power. (It was my first time using one.) I actually had black smoke come out of the muffler on several occasions (I think that the black was from burning oil). Anyways, I think that the ignition coil was broken before I stored it away for the winter. My improper storage made it harder to identify the problem, but I took some precautions to reduce the chance of it failing again. First, I turned down the idle speed (as it was pretty high). Second, I put some plastic washers between the ignition coil and the engine housing to reduce the amount of heat that it can absorb at once. And finally, I also oiled the crankshaft with some 2-cycle oil to reduce the head produced. Of course, the easiest way to prevent an overheat is to just run it slower, which I have been doing, but when I need it, it still has great power. Anyways, learn from my mistakes, and if you have a similar problem, maybe this will help you identify it.

Broken Dremel

Just the other day I was working on a project, and decided to fire up the old dremel. It turned out that my plans were about to change, as I accidentally broke it. Yes! I broke a tool. It turned on just fine but the switch got stuck in between the on and off setting.

It started revving up and down as I tried to get it all the way on or back off, but the button wouldn’t budge! Smoke started to pour out the ventilation grate, and I speedily unplugged it from the wall. So, what next, it’s broken right?

Well, after waiting couple hours for any potentially dangerous capacitors to discharge, I set out on a repair mission. When I opened it up, the culprit was immediately identifiable.

Burnt Button

Here is the button that I removed from the dremel. Notice anything wrong? The bottom was all burnt, and it smelled horrible too. In case you’re wondering, yes, it’s still stuck.

Lucky for me, my dad has a stash of old electronics in the closet, and as it turned out there was a near identical button in there. Here is what it looks like after some de-soldering and cleaning.

New Button

Yes, I know it is a DPST (double pole) switch, but when I say identical, I really meant it has the same voltage, amperage ratings, and it fits. As you can see in the picture, I just covered up one sides terminals with heat shrink to ensure insulation.

Here is what the insides of the dremel looked like when disassembled.

Inside the Dremel

The button is just connected with those two female electrical sleeves, and the wheel down there is the potentiometer for speed settings.

Nothing else looked burnt, so I wired it all up and gave it a go (ready to unplug it from the wall at any indication of smoke).

Fixed Dremel

It worked just like before, and after a minute of running at full speed, there are no apparent problems. I’m sure glad to have this tool back working again!

Relay and Thermistor

I have been tweaking my Arduino project lately and have got some decent results. I started by setting up the relay and thermistor separately. The plan was to turn on and off a fan based on when the room was hot or cold. Of course the hot and cold values were just our preference as set in the Arduino’s code.

Here is what the current prototype looks like.

Arduino Thermistor Relay Box

Graphing the serial output was something that helped us choose what temperature to turn on and off at. It currently sits near the heater and helps to circulate the warm air.